Titolo | Impedance and lithium-7 NMR studies of polymer electrolytes based on poly(vinylidene fluoride) |
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Tipo di pubblicazione | Articolo su Rivista peer-reviewed |
Anno di Pubblicazione | 1996 |
Autori | Croce, F., Appetecchi Giovanni Battista, Slane S., Salomon M., Tavarez M., Arumugam S., Wang Y., and Greenbaum S.G. |
Rivista | Solid State Ionics |
Volume | 86-88 |
Paginazione | 307-312 |
ISSN | 01672738 |
Parole chiave | Dibutylphthalate, Dimethylformamide, Impedance spectroscopy, Lithium batteries, Lithium compounds, Lithium salts, Nuclear magnetic resonance spectroscopy, Organic solvents, Plasticizers, Polyelectrolytes, Polyvinylidene fluoride, Spectroscopy, Vinyl resins |
Abstract | Composite polymer electrolytes consisting of at least 35 mol% poly(vinylidene fluoride) (PVdF) and mixtures of propylene carbonate (PC) and dimethyl formamide (DMF), lithium salts (LiAsF6, LiN(CF3SO2)2, or LiC(CF3SO2)3, and small amounts (∼ 5 mol%) of plasticizer, either diethylphthalate (DEP) or dibutylphthalate (DBP), were investigated by differential scanning calorimetry, complex impedance analysis and 7Li NMR spectroscopy. Despite the composite nature of these materials, they all exhibit a single glass transition temperature (Tg). Significant variations of Tg with the two different plasticizers were noted. The sample containing the LiC(CF3SO2)3 salt has the highest electrical conductivity of the series, ∼ 3 × 10 4S/cm at 25°C. Time-dependent impedance measurements utilizing cells with lithium electrodes revealed the growth of a passivating interface layer comparable to those observed with other polymer electrolytes. The onset of NMR motional line-narrowing is correlated with Tg for all samples prepared with DBP, as is known to occur in 'single component' polyether-based electrolytes. However the onset of narrowing for the samples containing DEP occurs about 30 K above Tg. Lithium-7 spin-lattice relaxation measurements exhibit non-exponential recovery profiles below Tg, with about ∼ 15% of the Li species relax differently than the majority. Activation energies extracted from 7Li T1 data show that localized Li motion is significantly impeded in the DEP-containing samples, relative to those prepared with DBP. |
Note | cited By 34 |
URL | https://www.scopus.com/inward/record.uri?eid=2-s2.0-0030182575&doi=10.1016%2f0167-2738%2896%2900137-3&partnerID=40&md5=7c05a6177b3859ae3dbd155d38b1a27c |
DOI | 10.1016/0167-2738(96)00137-3 |
Citation Key | Croce1996307 |